CN116991117B - Rapid programming method for personalized part machining - Google Patents
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- G05B—CONTROL OR REGULATING SYSTEMS IN GENERAL; FUNCTIONAL ELEMENTS OF SUCH SYSTEMS; MONITORING OR TESTING ARRANGEMENTS FOR SUCH SYSTEMS OR ELEMENTS
- G05B19/00—Programme-control systems
- G05B19/02—Programme-control systems electric
- G05B19/18—Numerical control [NC], i.e. automatically operating machines, in particular machine tools, e.g. in a manufacturing environment, so as to execute positioning, movement or co-ordinated operations by means of programme data in numerical form
- G05B19/4093—Numerical control [NC], i.e. automatically operating machines, in particular machine tools, e.g. in a manufacturing environment, so as to execute positioning, movement or co-ordinated operations by means of programme data in numerical form characterised by part programming, e.g. entry of geometrical information as taken from a technical drawing, combining this with machining and material information to obtain control information, named part programme, for the NC machine
- G05B19/40937—Numerical control [NC], i.e. automatically operating machines, in particular machine tools, e.g. in a manufacturing environment, so as to execute positioning, movement or co-ordinated operations by means of programme data in numerical form characterised by part programming, e.g. entry of geometrical information as taken from a technical drawing, combining this with machining and material information to obtain control information, named part programme, for the NC machine concerning programming of machining or material parameters, pocket machining
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Abstract
The invention discloses a rapid programming method for numerical control machining of personalized parts, which comprises the following steps: sampling data points on the surface of the part; constructing a processing feasible point set for the undercut part according to the profile band of the part; extracting a theoretical knife contact set in a knife position source file; taking the feasible point set as a deformation target, deforming the theoretical tool contact set based on Gaussian probability distribution, and reversely calculating tool points of the deformed discrete point set according to the type of the tool and the processing method; and rewriting the reversely calculated tool position points to generate a machining process tool position source file suitable for the current part. The invention provides a quick programming method for the processing of the thin-wall part, reduces the high rejection rate of the thin-wall part caused by undercutting and overcutting, and improves the processing precision and efficiency of the thin-wall part.
Description
Technical Field
The invention relates to the technical field of machining and manufacturing, in particular to a rapid programming method for personalized part machining.
Background
In order to realize high-efficiency and high-quality manufacture of aviation parts, the combined machining of the hot forming manufacture and the numerical control milling is the main manufacturing mode of the current thin-wall parts. The traditional thin-wall part is formed from an integral blank to a final part, numerical control material reduction processing is needed to be carried out on the blank for many times, the production period of the part is long, and the material removal rate is high. In the structural part in the aviation field, materials are often difficult to process, which are represented by titanium alloy, and the materials are high in price, so that the structural part in the aviation field has high cost. At present, the thin-wall part is often formed in a near-net shape, only a small amount of machining allowance is reserved after the part is formed, and the allowance is removed through machining methods such as numerical control milling and grinding, so that the manufacturing period of the thin-wall part is greatly shortened, and the material cost is reduced. However, due to the influence of factors such as temperature fluctuation, die abrasion, thermal deformation and the like in the near net forming process, the appearance of the thin-wall part after thermal forming has deviation from the theoretical shape, so that the machining allowance distribution is uneven or even insufficient, partial region undercut or out-of-tolerance in profile degree and thickness occur in the milling process, and the manufacturing precision of aviation parts is directly influenced or even scrapped. At present, the machining precision of parts is improved mainly through operations such as manual correction, polishing and the like, and the parts are longer in production period and poor in quality consistency due to severe dependence on the operation skills and experiences of workers.
The prior art generally adopts a discrete method such as mirror image compensation to pre-compensate the contour error. The invention of the patent number CN1 16107262A discloses a contour error precompensation method based on global analysis and reconstruction of a numerical control machining path, which aims to analyze and reconstruct an integral tool path under the condition of zero contour error, thereby effectively improving the precision of numerical control machining contours. According to the method, a contour error precompensation model of a global processing path is established through analysis, so that a complex contour error precompensation problem is converted into a reconstruction solution problem of an actual spline path control point, and global optimization adjustment of a contour error vector is realized. The invention solves the problem of shape following processing of parts, and aims to ensure the smoothness of the processing surface of the parts, and the contour tolerance zone of the parts is not involved, namely, the problem that the contour of the molded surface meets the tolerance requirement while ensuring the smoothness of the processing surface of the parts. The invention of patent number CN115146405A discloses a thin-wall part model reconstruction method based on non-rigid registration deformation, which comprises the following steps: 1) Sampling data points on the surface of the part blank, and carrying out pretreatment operations such as denoising, sequencing and the like on the sampling points; 2) Taking the sampling point set as a matching target, and carrying out rigid registration on the theoretical CAD model of the part and the preprocessed sampling points; 3) And acquiring cross section lines of different positions of the registered theoretical CAD model by adopting an isocross section method and intersecting operation, and dispersing the cross section lines into point sets by adopting an isoparametric method. Taking the sampling point set as a deformation target, deforming the discrete point set of the theoretical section line based on Gaussian probability distribution, and generating the section line by adopting NURBS curve interpolation on the deformed discrete point set; 4) And generating a CAD model adapting to the processing technology of the current part by a lofting section line method. The invention solves the problem that the machining allowance is insufficient due to the fact that the geometric shape of an actual blank of the thin-wall part cannot be enveloped with a theoretical CAD model caused by thermoforming deformation, namely the invention also solves the problem of undercutting caused by insufficient machining allowance, ensures the smoothness of the machining surface of the part, and does not consider the contour tolerance requirement of the molded surface of the part; the patent also needs the steps of importing the model into the three-dimensional software again according to the reconstruction model, selecting the processing area, generating the processing path, post-processing and the like. None of the foregoing methods involve optimization of the programming method for personalized part manufacturing.
Disclosure of Invention
The invention provides a rapid programming method for processing personalized parts, which aims at easily deformed thin-wall parts, and adopts a non-rigid registration deformation means for theoretical knife contacts, so that the deformed knife contacts can be surrounded by the shape of an actual blank, namely, the uniform machining allowance is provided, and the personalized customization of theoretical knife position files of the thin-wall parts is realized.
In order to achieve the technical purpose, the invention adopts the following technical scheme:
a rapid programming method for personalized part machining, the rapid programming method comprising the steps of:
s1, sampling data points on the surface of a part blank through a contact probe or a non-contact point laser displacement sensor, and denoising and sequencing the sampling points to obtain a preprocessed sampling point set;
s2, dispersing the part tolerance zone surface into a discrete point set which is the same as the sampling point number, and registering with the preprocessed sampling point set to calculate a feasible point set of the part tolerance zone surface;
s3, extracting a theoretical knife contact set in a processing technology knife position source file of the current part; taking the feasible point set as a deformation target, and deforming the theoretical knife contact set based on Gaussian probability distribution to obtain the feasible knife contact set;
s4, solving based on the feasible cutter contact set to obtain a back-calculation cutter position according to the cutter type and the machining method, and rewriting the back-calculation cutter position into a machining process cutter position source file of the current part.
Further, in step S1, the process of sampling the data points on the surface of the part by using the contact probe or the non-contact point laser displacement sensor includes the following steps:
carrying out data point sampling planning on the surface of the CAD model of the part by adopting a chord height difference method, fitting a point set of a planned sampling area into a curve, comparing the curve with the deviation of the CAD model of the part, selecting the precision required by the contour degree processing of the part line as a chord tolerance, and taking the precision as a constraint condition for optimizing the sampling points, wherein the distribution of the sampling points at the curvature abrupt change position of the part is more than that of the sampling points at the smooth position;
based on the data point sampling plan, the sampling point data is processed into a numerical control measuring program identified by the machine tool, and the data point sampling is carried out on the surface of the part through a contact probe or a non-contact point laser displacement sensor.
Further, in step S1, the process of denoising and sorting the sampling points includes the following steps:
setting a deviation threshold value, and removing noise points of the curved surface contour, the deviation value of which is larger than the deviation threshold value, from the sampling points;
and sorting the denoised sampling points, wherein the sorted point set sequence is the same as the measurement sequence, and the self-intersection of the curves can not occur during fitting.
Further, in step S2, the process of dispersing the part tolerance zone surface into a discrete point set identical to the sampling points, and registering with the sampling points to calculate a feasible point set of the part tolerance zone surface includes the following steps:
modeling a part theoretical tolerance zone in three-dimensional modeling software, dispersing a NURBS tolerance zone curved surface by adopting an isoparametric method, and obtaining coordinate values of discrete points according to coordinate values of each point on the NURBS tolerance zone curved surface:
wherein d ij To control the vertex, ω ij As a weight factor, N i，k (u) and N j，l (v) B spline basis functions in the u-direction k times and the v-direction l times respectively; the values of the parameters u and v are all 0,1]Equally dividing the two into n parts according to the number of the feasible points; p (u, v) is a curved surface type value point, u and v are two parameter directions of a curved surface respectively, i and j are numbers of control vertexes in u and v directions respectively, m and n are total numbers of control vertexes in u and v directions respectively, and k and l are times of B spline curves in u and v directions respectively;
registering the discrete points with the sampling points based on the weights, and calculating to obtain a feasible point set:
wherein,as a feasible point +.>For measuring points, the->As tolerance band discrete points, λ is a weight factor.
Further, in step S3, the process of extracting the theoretical tool contact set in the machining process tool bit source file of the current part includes the following steps:
s31, importing a template cutter position file;
s32, reading data line by line, judging whether GOTO characters exist in the current line, if so, turning to a step S33, otherwise, turning to a step S34;
s33, judging whether the current line has the character, if so, recording the knife contact data after the character;
s34, judging whether the template cutter point file is read completely, if not, adding one to the number of rows of the current row, turning to the step S32, otherwise, outputting all recorded cutter contact point data as a theoretical cutter contact point set, and ending the flow.
Further, in step S3, with the feasible point set as a deformation target, the process of deforming the theoretical knife contact set based on gaussian probability distribution to obtain the feasible knife contact set includes the following steps:
the feasible point set and the theoretical knife contact set are used as input, the feasible point set is used as a deformation target, the corresponding relation between point pairs is established, and the probability density p (x) between the feasible point set and the theoretical knife contact set is calculated by adopting the following formula:
and (3) solving a transformation matrix corresponding to the maximum value of p and a transformed knife contact set through optimization iteration, and setting deformation between the knife contact set and a feasible point set based on Gaussian probability distribution.
Further, in step S4, for the side milling, the solution formula of the back-calculation tool point is:
in the method, in the process of the invention,for the knife site of the knife, the->For a viable knife contact, R is the knife radius, < >>Is a theoretical contour unit normal vector.
Further, in step S4, for the end mill processing, the solution formula of the back-calculation tool point is:
in the method, in the process of the invention,for the knife site of the knife, the->For a viable knife contact, R is the knife radius, R is the fillet radius, +.>For theoretical contour unit normal ++>Is a cutter shaft unit normal vector; when a fillet milling cutter is used, the value of r is determined according to the geometric dimension of the cutter; when a ball nose milling cutter is used, r=r; when using a flat bottom milling cutter, r=0.
Further, in step S4, the process of rewriting the back calculated tool position point into the machining process tool position source file of the current part includes the following steps:
s41, importing a template cutter position file;
s42, reading data line by line, judging whether GOTO characters exist in the current line, if so, turning to a step S43, otherwise, turning to a step S44;
s43, judging whether the current line has the character $ or not, if the character $ is read, writing the back calculated cutter point data into the GOTO character;
s44, judging whether the reading of the template cutter point file is finished, if not, adding one to the number of lines of the current line, turning to the step S32, otherwise, outputting the template cutter point file subjected to copying, and finishing the flow.
Compared with the prior art, the invention has the following beneficial effects:
the rapid programming method for personalized part machining solves the problem that the actual geometric shape of the thin-wall part cannot surround the machining allowance of a theoretical CAD model due to the near-net-shape forming thermal process, reduces the high rejection rate of the thin-wall part caused by undercutting and overcutting, and effectively improves the machining precision and efficiency of the thin-wall part.
The rapid programming method for personalized part processing, provided by the invention, omits complicated steps in the prior art such as reintroducing a model into three-dimensional software according to a reconstruction model, selecting a processing area, generating a processing path, performing post-processing and the like while considering the profile tolerance of the part, directly generates a processable guide rail file without human intervention, and realizes rapid customized processing of the personalized part.
Drawings
FIG. 1 is a flow chart of a method of fast programming for personalized part machining of the present invention;
FIG. 2 is a schematic diagram of a feasible point acquisition of the present invention;
fig. 3 is a schematic representation of non-rigid registration of the present invention.
Detailed Description
Embodiments of the present invention are described in further detail below with reference to the accompanying drawings.
The invention discloses a rapid programming method for personalized part processing, which comprises the following steps:
s1, sampling data points on the surface of a part blank through a contact probe or a non-contact point laser displacement sensor, and denoising and sequencing the sampling points to obtain a preprocessed sampling point set;
s2, dispersing the part tolerance zone surface into a discrete point set which is the same as the sampling point number, and registering with the preprocessed sampling point set to calculate a feasible point set of the part tolerance zone surface;
s3, extracting a theoretical knife contact set in a processing technology knife position source file of the current part; taking the feasible point set as a deformation target, and deforming the theoretical knife contact set based on Gaussian probability distribution to obtain the feasible knife contact set;
s4, solving based on the feasible cutter contact set to obtain a back-calculation cutter position according to the cutter type and the machining method, and rewriting the back-calculation cutter position into a machining process cutter position source file of the current part.
As shown in FIG. 1, the present invention relates to fast programming techniques, digital measurement techniques, computer graphics techniques, and the like. The invention discloses a rapid programming method for personalized part processing, which mainly comprises five parts: data preparation, feasible point acquisition, knife contact extraction, deformation based on Gaussian probability distribution and knife position point copying.
The data preparation process is as follows: firstly, carrying out data point sampling planning on the surface of a CAD model of the part by adopting a chord height difference method, fitting a point set of a planned sampling area into a curve, carrying out deviation comparison on the curve and the CAD model of the part, selecting the precision required by the contour degree processing of the part line as chord tolerance, taking the precision as a constraint condition for optimizing sampling points, and carrying out more distribution of sampling points at the curvature abrupt change of the part, wherein the smooth part is less, and the change of the appearance characteristics of the part is reflected. And then processing the sampling point data into a numerical control measuring program which can be identified by a machine tool through a configured post-processing program, and starting to measure the appearance of the actual blank. After the measurement is finished, the measurement point data is checked, noise points which obviously deviate from the curve profile are eliminated, and the surface of the point set reflects the curve characteristics smoothly. And then sorting the denoised measurement points, wherein the sorting principle is that the ordered point set order is the same as the measurement order, and the self-intersection of the curves cannot occur in the subsequent fitting. Because the reflection characteristic of the metal surface and the cleanliness of the part surface all influence the point laser displacement sensor, noise points, namely unreasonable outliers, are sometimes doped in the sampled data points. Therefore, redundant and abnormal points are removed by denoising the sampling points, so that the data of the sampling points are simplified, and the operation rate is improved; the sampled data points are then ordered to prevent self-intersection of the curve during subsequent data point fitting.
The specific process of obtaining the feasible points is as follows: firstly modeling a part theoretical tolerance zone in three-dimensional modeling software, and then dispersing NURBS tolerance zone curved surfaces by adopting an isoparametric method, wherein the mathematical expression of the NURBS curved surfaces is shown as (1):
wherein d ij To control the vertex, ω ij Is a weight factor Nx ，k (u) and N j，l (v) B-spline basis functions are respectively u-way k-way and v-way l-way.
The value range of the parameters u and v is 0 and 1, the parameters u and v are equally divided into n parts according to the number of the required feasible points by an isoparametric method, and the coordinate value of the corresponding point is obtained according to the formula (1) according to the coordinate value of each point. And then calculating the actual measurement point set and the feasible point set by a weight-based method to obtain the feasible point set (shown in figure 2), wherein the mathematical expression is shown in (2):
wherein,as a feasible point +.>For measuring points, the->As tolerance band discrete points, λ is a weight factor.
When the template cutter contact point extraction is carried out, firstly, the row where the GOTO sentence is located is identified, wherein the GOTO sentence comprises a cutter fast-forward section and an actual cutting section, and the difference is that data points are separated by the actual cutting section, the cutter position information is the front of the data points, and the cutter contact point information is the rear of the data points. The specific process of knife contact extraction is as follows: importing a template cutter position file, reading a first row, and if GOTO characters are read, continuing to read; if not, jumping to the next row until the GOTO character is read. Judging whether the GOTO character is read or not after the GOTO character is read, if the GOTO character is read, recording the cutter contact data after the GOTO character, and jumping to the next row; if not, jumping to the next row. The knife contact extraction is completed when the last row read is completed.
The non-rigid deformation is specifically as follows: taking a data point set obtained by calculation (hereinafter simply referred to as a feasible point set) and a tool contact point set obtained by a theoretical tool bit file (hereinafter simply referred to as a tool contact point set) as inputs, taking the feasible point set as a deformation target, establishing a corresponding relation between point pairs, obtaining a probability density p between the feasible point set and the theoretical tool contact point set according to a formula (3), then solving a transformation matrix T corresponding to the maximum value of p and the transformed tool contact point set through optimization iteration, thereby realizing deformation between the tool contact point set and the feasible point set based on Gaussian probability distribution (as shown in figure 3)
Next, the solution of the tool point needs to be performed according to the machining mode and the tool type, and for the side milling machining, the mathematical expression is as follows:
in the method, in the process of the invention,for the knife site of the knife, the->For a viable knife contact, R is the knife radius, < >>Is a theoretical contour unit normal vector.
For the end mill processing, the mathematical expression is:
in the method, in the process of the invention,for the knife site of the knife, the->Is a feasible knife contact, R is a knife radius, and R is a circleCorner radius->For theoretical contour unit normal ++>Is a cutter shaft unit normal vector; when a fillet milling cutter is used, the value of r is determined according to the geometric dimension of the cutter; when a ball nose milling cutter is used, r=r; when using a flat bottom milling cutter, r=0.
And (3) performing back calculation on the non-rigidly deformed cutter contact to obtain a feasible cutter position point, and performing post-treatment on the feasible cutter position point to generate a personalized numerical control machining program adapting to the appearance of the part. The specific process of copying the knife site is as follows: and reversely calculating the deformed cutter contact point as a cutter position point according to the machining process and the geometric parameters of the cutter. Importing a template cutter position file, reading a first row, and if GOTO characters are read, continuing to read; if not, jumping to the next row until the GOTO character is read. Judging whether the GOTO character is read or not after the GOTO character is read, if the GOTO character is read, writing the back calculated tool bit point data into the GOTO character, and jumping to the next row; if not, jumping to the next row. And when the reading of the last row is finished, the copying of the cutter bit point is finished.
The invention provides a quick programming method for processing the thin-wall part, solves the problem that the geometrical shape of an actual blank of the thin-wall part caused by thermoforming deformation cannot be enveloped with a theoretical model CAD model, namely, the machining allowance is insufficient, reduces the high rejection rate of the thin-wall part caused by undercutting and overcutting, and improves the processing precision and efficiency of the thin-wall part.
It will be appreciated by those skilled in the art that embodiments of the present application may be provided as a method, system, or computer program product. Accordingly, the present application may take the form of an entirely hardware embodiment, an entirely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, the present application may take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, and the like) having computer-usable program code embodied therein. The solutions in the embodiments of the present application may be implemented in various computer languages, for example, object-oriented programming language Java, and an transliterated scripting language JavaScript, etc.
The present application is described with reference to flowchart illustrations and/or block diagrams of methods, apparatus (systems) and computer program products according to embodiments of the application. It will be understood that each flow and/or block of the flowchart illustrations and/or block diagrams, and combinations of flows and/or blocks in the flowchart illustrations and/or block diagrams, can be implemented by computer program instructions. These computer program instructions may be provided to a processor of a general purpose computer, special purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, create means for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.
These computer program instructions may also be stored in a computer-readable memory that can direct a computer or other programmable data processing apparatus to function in a particular manner, such that the instructions stored in the computer-readable memory produce an article of manufacture including instruction means which implement the function specified in the flowchart flow or flows and/or block diagram block or blocks.
These computer program instructions may also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer implemented process such that the instructions which execute on the computer or other programmable apparatus provide steps for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.
While preferred embodiments of the present application have been described, additional variations and modifications in those embodiments may occur to those skilled in the art once they learn of the basic inventive concepts. It is therefore intended that the following claims be interpreted as including the preferred embodiments and all such alterations and modifications as fall within the scope of the application.
It will be apparent to those skilled in the art that various modifications and variations can be made in the present application without departing from the spirit or scope of the application. Thus, if such modifications and variations of the present application fall within the scope of the claims and the equivalents thereof, the present application is intended to cover such modifications and variations.
Claims (9)
1. A rapid programming method for personalized part machining, characterized in that the rapid programming method comprises the following steps:
s1, sampling data points on the surface of a part blank through a contact probe or a non-contact point laser displacement sensor, and denoising and sequencing the sampling points to obtain a preprocessed sampling point set;
s2, dispersing the part tolerance zone surface into a discrete point set which is the same as the sampling point number, and registering with the preprocessed sampling point set to calculate a feasible point set of the part tolerance zone surface;
s3, extracting a theoretical knife contact set in a processing technology knife position source file of the current part; taking the feasible point set as a deformation target, and deforming the theoretical knife contact set based on Gaussian probability distribution to obtain the feasible knife contact set;
s4, solving based on the feasible cutter contact set to obtain a back-calculation cutter position according to the cutter type and the machining method, and rewriting the back-calculation cutter position into a machining process cutter position source file of the current part.
2. The method of claim 1, wherein in step S1, the process of sampling data points on the surface of the part by using a contact probe or a non-contact point laser displacement sensor comprises the following steps:
carrying out data point sampling planning on the surface of the CAD model of the part by adopting a chord height difference method, fitting a point set of a planned sampling area into a curve, comparing the curve with the deviation of the CAD model of the part, selecting the precision required by the contour degree processing of the part line as a chord tolerance, and taking the precision as a constraint condition for optimizing the sampling points, wherein the distribution of the sampling points at the curvature abrupt change position of the part is more than that of the sampling points at the smooth position;
based on the data point sampling plan, the sampling point data is processed into a numerical control measuring program identified by the machine tool, and the data point sampling is carried out on the surface of the part through a contact probe or a non-contact point laser displacement sensor.
3. The rapid programming method for personalized parts machining according to claim 1, wherein in step S1, the process of denoising and sorting the sampling points comprises the following steps:
setting a deviation threshold value, and removing noise points of the curved surface contour, the deviation value of which is larger than the deviation threshold value, from the sampling points;
and sorting the denoised sampling points, wherein the sorted point set sequence is the same as the measurement sequence, and the self-intersection of the curves can not occur during fitting.
4. The method of claim 1, wherein in step S2, the process of discretizing the part tolerance zone surface into a set of discrete points equal to the number of sampling points and registering with the sampling points to calculate a set of feasible points for the part tolerance zone surface comprises the steps of:
modeling a part theoretical tolerance zone in three-dimensional modeling software, dispersing a NURBS tolerance zone curved surface by adopting an isoparametric method, and obtaining coordinate values of discrete points according to coordinate values of each point on the NURBS tolerance zone curved surface:
wherein d ij To control the vertex, ω ij As a weight factor, N i，k (u) and N j，l (v) B-spline basis functions in the u-direction k times and the v-direction 1 times respectively; the values of the parameters u and v are all 0,1]Equally dividing the two into n parts according to the number of the feasible points; p (u, v) is a curved surface type value point, u and v are two parameter directions of the curved surface respectively, and i and j are control vertexes in u and v respectivelyThe numbers of the directions, m and n are the total number of control vertexes in the u and v directions respectively, and k and l are the times of B spline curves in the u and v directions respectively;
registering the discrete points with the sampling points based on the weights, and calculating to obtain a feasible point set:
wherein,as a feasible point +.>For measuring points, the->As tolerance band discrete points, λ is a weight factor.
5. The method according to claim 1, wherein in step S3, the process of extracting the theoretical tool contact set in the tool position source file of the current processing technology of the part comprises the following steps:
s31, importing a template cutter position file;
s32, reading data line by line, judging whether GOTO characters exist in the current line, if so, turning to a step S33, otherwise, turning to a step S34;
s33, judging whether the current line has the character, if so, recording the knife contact data after the character;
s34, judging whether the template cutter point file is read completely, if not, adding one to the number of rows of the current row, turning to the step S32, otherwise, outputting all recorded cutter contact point data as a theoretical cutter contact point set, and ending the flow.
6. The method for rapid programming for personalized parts machining according to claim 1, wherein in step S3, the process of deforming the theoretical tool contact set based on gaussian probability distribution with the feasible contact set as a deformation target to obtain the feasible tool contact set comprises the following steps:
taking a feasible point set and a theoretical knife contact set as input, taking the feasible point set as a deformation target, establishing a corresponding relation between point pairs, and calculating Gaussian probability density p between the feasible point set and the theoretical knife contact set:
and solving a transformation matrix corresponding to the maximum value of p, and carrying out deformation based on Gaussian probability distribution on the theoretical knife contact set.
7. The method according to claim 1, wherein in step S4, for the side milling process, the solution formula of the back-calculation tool position is:
in the method, in the process of the invention,for the knife site of the knife, the->For a viable knife contact, R is the knife radius, < >>Is a theoretical contour unit normal vector.
8. The method of claim 1, wherein in step S4, for the end mill machining, the solution formula for the back-calculation tool position is:
in the method, in the process of the invention,for the knife site of the knife, the->For a viable knife contact, R is the knife radius, R is the fillet radius, +.>For theoretical contour unit normal ++>Is a cutter shaft unit normal vector; when a fillet milling cutter is used, the value of r is determined according to the geometric dimension of the cutter; when a ball nose milling cutter is used, r=r; when using a flat bottom milling cutter, r=0.
9. The method according to claim 1, wherein in step S4, the step of rewriting the back calculated tool bit point into the machining process tool bit source file of the current part comprises the steps of:
s41, importing a template cutter position file;
s42, reading data line by line, judging whether GOTO characters exist in the current line, if so, turning to a step S43, otherwise, turning to a step S44;
s43, judging whether the current line has the character $ or not, if the character $ is read, writing the back calculated cutter point data into the GOTO character;
s44, judging whether the reading of the template cutter point file is finished, if not, adding one to the number of lines of the current line, turning to the step S32, otherwise, outputting the template cutter point file subjected to copying, and finishing the flow.
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